zlib: don't assert on malformed dictionary

Handle Z_DATA_ERROR errors from inflateSetDictionary() gracefully.
Fixes the following assertion:

  node: ../src/node_zlib.cc:167: static void node::ZCtx::Process
  (uv_work_t*): Assertion `ctx->err_ == 0 && "Failed to set
  dictionary"' failed.
  Aborted (core dumped)

Fixes #4632.

1 files changed, 12 insertions, 0 deletions

diff --git a/test/simple/test-zlib-dictionary-fail.js b/test/simple/test-zlib-dictionary-fail.js
index f6d186990..fd35a0192 100644
--- a/test/simple/test-zlib-dictionary-fail.js
+++ b/test/simple/test-zlib-dictionary-fail.js
@@ -34,3 +34,15 @@ var zlib = require('zlib');
   // String "test" encoded with dictionary "dict".
   stream.write(Buffer([0x78,0xBB,0x04,0x09,0x01,0xA5]));
 })();
+
+// Should raise an error, not trigger an assertion in src/node_zlib.cc
+(function() {
+  var stream = zlib.createInflate({ dictionary: Buffer('fail') });
+
+  stream.on('error', common.mustCall(function(err) {
+    assert(/Bad dictionary/.test(err.message));
+  }));
+
+  // String "test" encoded with dictionary "dict".
+  stream.write(Buffer([0x78,0xBB,0x04,0x09,0x01,0xA5]));
+})();